Self-closing manual dispenser

ABSTRACT

A manual dispenser dispenses a liquid substance by pressure, and automatically closes in the absence of pressure. The dispenser has a push button for controlling an aerosol valve or pump, or a stopper for a receptacle having flexible, compressible walls. The dispenser is characterized in that it comprises a nozzle ( 3 ) with an elastically deformable distribution slot ( 7 ) which nozzle is integrated by molding into a relatively rigid body ( 1 ).

The present invention relates to the packaging industry and to theplastics moulding industry.

It is aimed more specifically at the dispensing of fluid substances:liquids, emulsions, gels, particularly cosmetic or pharmaceutical,conveyed by pressure into a discharge duct the outlet of which is closedautomatically in the absence of pressure, so as to avoid deteriorationof the substance remaining in the duct and to ensure that the dischargeorifice remains clean. It relates most specifically to closure meansemploying an elastic diaphragm pierced with a slit.

At rest, the walls of the slit press elastically against one another andclose the duct. When a dispensing push-button controlling an aerosolvalve or a pump is pressed, or if pressure is applied to a containerwith compressible flexible walls, such as a tube or pouch, sealed by astopper equipped with such a duct, the substance ejected under pressureparts the walls or lips of the slit so that it can be dispensed. As soonas the pressure ceases, the slit closes back up and closes the dischargeduct.

BACKGROUND OF THE INVENTION

Such a self-closing device is described particularly in the BOUET Frenchpatent number 1 351 565 in its application to flexible bottles or tubes.

According to this patent, the dispensing slit is cut in a thin wall thatcloses the neck and is formed at the time of moulding from the materialof the container. When this device needs to be adapted to a push-buttonor to a stopper that is screwed on or forcibly inserted into or onto theneck of a container, then a material that can withstand the mechanicalstresses of fitting and retaining the stopper or of actuating thepush-button must be used to form the body. Such material does notsatisfy the elasticity requirements of the dispensing slit. It istherefore necessary to use two different materials for the slit and forthe body. It has already been proposed, for example in documents EP 0743 259 A and 0 442 379 A, for a container stopper comprising a slitmembrane to be produced by a two-shot injection-moulding method.However, a slit diaphragm such as this needs a very special and wideconfiguration of stopper which is well suited to the dispensing ofhighly viscous liquids or pastes (such as a toothpaste or gel) but israther ill-suited to the dispensing of more fluid substances, especiallythose whose release is usually controlled by a system of the aerosolvalve type, for which a dispensing nozzle that consists of an elongatetubular passage is preferred. In the prior art, a nozzle of this kind isillustrated by document GB 1 472 178, and consists of a passage mouldedin the body transversely to an axial central duct (sitting on the hollowpump- or valve-actuating stem), the entire assembly being produced bymoulding in a body which also has an upper surface for pressing on and aperipheral skirt.

If there is the desire to equip such a nozzle with a self-closing slit,the solution of producing a slit diaphragm by two-shot injectionmoulding is not suitable, as has been seen. From another viewpoint, ifthe nozzle is made separately and as a single piece with an end partthat comprises the self-closing slit made of a material that is flexibleenough for this, then the problem of incorporating the slit-comprisingnozzle into the body of the container arises. The problem is that ifsuch a nozzle is simply inserted into a housing in the body, then theretaining forces need to be higher than the forces tending to expel thenozzle under the pressure of the fluid substance being dispensed. Thisleads to the need for precise dimensioning of the nozzle and of thehousing in order to ensure correct retention without deformation of thenozzle. It is difficult to achieve such precision under mass-productionindustrial moulding conditions, particularly given gradual mould wear.

SUMMARY OF THE INVENTION

The object of the invention is a self-closing dispenser which does notexhibit such drawbacks and lends itself well to industrial manufactureat competitive cost.

The subject of the invention is a manual dispenser of fluid substancesusing pressure, which closes automatically in the absence of pressure,having a push-button for controlling an aerosol valve or pump type, or astopper for a compressible flexible-walled container type, of the kindwhich has an elastically deformable self-closing dispensing slitincorporated by moulding into a relatively rigid body, characterized inthat the slit is made at one end of a one-piece nozzle made up of anelongate tubular element made of a relatively flexible and elasticmaterial, which is incorporated by moulding into the said body.

The tubular element advantageously ends in a wall through which the saidself-closing slit partially passes; advantageously, this wall has adome-shaped interior face, and it may have a flat exterior face.

It is advantageous for the slit to be formed in a slit bulging head ofthe nozzle, which head is clear of the body and extends the shapethereof, so as to leave the material of the nozzle free to actelastically without the constraint of being closely surrounded by therigid material of the body.

Advantageously, the body has an axial duct into which the nozzle or anextension thereof opens non-axially; the body also has an upper surfacefor pressing on and a peripheral skirt, and is designed to have an axialdirection of release from the mould.

As a preference, the nozzle points upwards and is designed so as to makean obtuse angle with the said axial direction, so as to make mouldingeasier, as will be seen later.

In practice, the nozzle may be made of an elastomer of theethylene-vinyl acetate type, and the body may be made of a polymer ofthe polypropylene type.

Another subject of the invention is a method of manufacturing such adispenser, characterized in that the nozzle is first moulded on its own,and then transferred into the body mould so that it can be incorporatedinto the body when the dispenser is moulded, and the end of the nozzleof the dispenser thus formed is then slit, either in the mould or as aseparate operation.

DETAILED DESCRIPTION OF THE DRAWINGS

A better understanding of the invention may be had from the detaileddescription of the appended drawings which depict two embodiments of theinvention chosen simply by way of example from numerous embodiments,adaptations and variants that might be envisaged by a competenttechnician.

In these drawings:

FIG. 1 is a diagrammatic view in axial section of a push-button forcontrolling an aerosol valve or a pump, according to the invention,

FIG. 2 is a view in front elevation of the push-button of FIG. 1;

FIG. 3 is a view from above of the same push-button;

FIG. 4 is a view similar to that of FIG. 1, of a container stopper,according to the invention;

FIG. 5 depicts in section that part of the mould that is used formoulding the nozzle;

FIG. 6 depicts the release from the mould of the nozzle produced in FIG.5;

FIG. 7 depicts the installing of that part of the mould that is used formoulding the body;

FIG. 8 depicts the moulding of the body;

FIG. 9 depicts the releasing of the body from the mould.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

In these figures, the elements which correspond are denoted by the samenumerical references, possibly given an index. In order to make thedrawings clearer, the respective proportions and dimensions of theseelements may not have been respected. The push-button depicted in FIGS.1 to 3 and 5 to 9 is made of one piece and formed by overmoulding arelatively rigid body 1 around the lower part 2 of a relatively elasticelongate tubular nozzle 3. The internal passage 4 of the nozzle ends ina dome 5 in a wall 6 that has a flat exterior face, pierced with a slit7. The opposite end of the nozzle opens into an axial tubular extension8 of the body 1 that is called upon to house the end of the hollowactuating stem 9 of an aerosol valve or of a pump, this stem being shownin broken line. The exterior part or head 10 of the nozzle 3 iscompletely clear of the body 1. The slit 7 does not therefore experiencethe constraint of being surrounded by the body 1 and can reactelastically to the influences of a fluid substance conveyed underpressure by the passage 4, to open and then close again automaticallywhen the pressure ceases. As known per se, the body 1 has a more or lesscylindrical and possibly domed peripheral skirt 14 connecting, at thetop, with a surface 15 for pressing on, which allows a downward pressureto be exerted with the fingers. The body is designed to allow axialrelease from the mould.

The nozzle 3 is arranged facing obliquely upwards, and the surface isfor pressing on is inclined.

In the stopper depicted in FIG. 4, the elements which correspond tothose of the push-button of FIGS. 1 to 3 are denoted by the samenumerical references, but given the index a. The lateral skirt 11 of thebody 1 a has internal screwthreads 12 intended to cooperate with thescrewthread of the neck 13 of a container, shown in broken line.

FIGS. 5 to 9 illustrate the production of the dispenser of FIG. 1.

First of all (FIG. 5) the nozzle 3 is moulded in a first moulding partof the mould, which part is made up of the parts A, C, D and B (pin orneedle for forming the internal passage 4).

In a second stage (FIG. 6), the pin B, then the part C and D formoulding the bottom 2 of the nozzle are removed, leaving the nozzle 3housed by its head 10 in the part A.

In a third stage (FIG. 7), the part A of the tooling, with the nozzle 3,is transferred into another moulding area part made up of the parts E,F, G and H. Transfer may be a translational or rotational movementwithin the mould. The axial pin F presses, via an appropriate stub fagainst the bottom 2 of the nozzle and thus seals off the passage 4.

In a fourth stage (FIG. 8), the body 1 is injected without filling thecavity 4, because of the aforementioned sealing-off.

Finally, release form the mould is achieved (FIG. 9) by withdrawing Aand E, parting the mould in the axial direction between H and G, andthen driving the part 1 off the pins F and G.

What is claimed is:
 1. A manual dispenser for dispensing fluidsubstances under pressure and which automatically closes in the absenceof pressure being applied thereto, comprising: a relatively rigid bodymember for being secured onto a container holding the fluid to bedispensed; and a nozzle having an elongated tubular passage and anelastically deformable self-closing dispensing slit formed at the distalend of said nozzle, said nozzle being made of a relatively flexible andelastic material and being incorporated into said rigid body member bymolding said body member around a major portion of an external surfaceof said nozzle along said elongated tubular passage.
 2. A dispenseraccording to claim 1, wherein the slit is formed in a bulging head ofthe nozzle, which head is clear of the body and extends the shapethereof.
 3. A dispenser according to claim 1, wherein the body memberincludes an upper surface for being pressed to dispense the fluid, and aperipheral skirt.
 4. A dispenser according to claim 1, wherein thenozzle is made of an ethylene-vinyl acetate elastomer, and the bodymember is made of a polypropylene polymer.
 5. A dispenser according toclaim 1, wherein the body member has an axial duct into which theproximal end of said tubular passage of said nozzle opens non-axially.6. A dispenser according to claim 5, wherein the nozzle is designed tomake an obtuse angle with the said axial duct.
 7. A dispenser accordingto claim 1, wherein the distal end of said tubular passage ends in awall through which said self-closing slit partially passes.
 8. Adispenser according to claim 7, wherein said wall has a dome-shapedinterior face.
 9. A dispenser according to claim 7, wherein said wallhas a flat exterior face.
 10. A method of manufacturing a manualdispenser for dispensing fluid substances under pressure and whichautomatically closes in the absence of pressure being applied thereto,wherein the manual dispenser has (1) a push-button for controlling anaerosol valve or pump; or (2) a stopper for a compressibleflexible-walled container having an elastically deformable self-closingslit incorporated by moulding into a relatively rigid body comprising:molding a nozzle from a relatively flexible and elastic material toinclude an elongated tubular passage; transferring said nozzle into abody mold; molding a body member from a material which is relativelyrigid in its finished state, said body member being molded around amajor portion of an external surface of said nozzle in said body member;and forming an elastically deformable self-closing dispensing slit atthe distal end of said nozzle.
 11. A method according to claim 10,further comprising temporarily sealing off said elongated tubularpassage with said body mold when molding said body member to avoidfilling said elongated tubular passage with said relatively rigidmaterial.
 12. A method according to claim 10, further comprising formingsaid body member to have a lateral skirt for receiving a neck of acontainer holding the fluid to be dispensed.
 13. A method according toclaim 10, further comprising forming said body member to have aperipheral skirt and an axial tube for receiving an actuating stem of acontainer holding the fluid to be dispensed.
 14. A method according toclaim 13, wherein said body member is formed with an upper surface forbeing pressed to dispense the fluid.